President Donald Trump and Supreme Court Chief Justice John Roberts are engaging in an extraordinary public dispute over the independence of America's judiciary, with Roberts bluntly rebuking the president for denouncing a judge who rejected Trump's migrant asylum policy as an "Obama judge."

Trump, still seething over that Monday ruling, began his Thanksgiving Day by asserting that the courts should defer to his administration and law enforcement on border security because judges "know nothing about it and are making our Country unsafe."

And taking aim at a co-equal branch of government, Trump said "Roberts can say what he wants" but the largest of the federal appellate courts, based in San Francisco and with a majority of judges appointed by Democratic presidents, "is a complete & total disaster." That's where an appeal of the asylum ruling would normally go.

Roberts had issued a strongly worded statement Wednesday defending judicial independence and contradicting Trump over his claim that judges are partisans allied with the party of the president who nominated them. Never silent for long, Trump responded with a "Sorry Justice Roberts" tweet.

The dustup is the first time that Roberts, the Republican-appointed leader of the federal judiciary, has offered even a hint of criticism of Trump, who has several times gone after federal judges who have ruled against him.